// Copyright (c) 2023 Muqiu Han
//
// All rights reserved.
//
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// modification, are permitted provided that the following conditions are met:
//
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//       this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above copyright
//     notice,
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//       may be used to endorse or promote products derived from this software
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#ifndef SWALLOW_COMPILER_G_MACHINE_ENVIRONMENT_HPP
#define SWALLOW_COMPILER_G_MACHINE_ENVIRONMENT_HPP

#include "utils/optional.hpp"
#include <memory>
#include <string>

namespace swallow::compiler::gmachine
{

  class Environment
  {
  public:
    using Ptr = std::shared_ptr<Environment>;

    virtual ~Environment() = default;

    [[nodiscard]] virtual auto GetOffset(const std::string &name) const noexcept -> tl::optional<int> = 0;

    [[nodiscard]] virtual auto HasVariable(const std::string &name) const noexcept -> bool = 0;
  };

  class Variable : public Environment
  {
  public:
    std::string Name;
    Ptr         Parent;

    Variable(std::string Name, Ptr Parent) : Name(std::move(Name)), Parent(std::move(Parent)) {}

    [[nodiscard]] auto GetOffset(const std::string &name) const noexcept -> tl::optional<int> override;

    [[nodiscard]] auto HasVariable(const std::string &name) const noexcept -> bool override;
  };

  class Offset : public Environment
  {
  public:
    uint32_t Value;
    Ptr      Parent;

    Offset(uint32_t Value, Ptr Parent) : Value(Value), Parent(std::move(Parent)) {}

    [[nodiscard]] auto GetOffset(const std::string &name) const noexcept -> tl::optional<int> override;

    [[nodiscard]] auto HasVariable(const std::string &name) const noexcept -> bool override;
  };

} // namespace swallow::compiler::gmachine

#endif /* SWALLOW_COMPILER_G_MACHINE_ENVIRONMENT_HPP */
